WASHINGTON — We’re in denial: Americans underestimate their chances of needing long-term care as they get older and are taking few steps to get ready. A new poll examined how people 40 and over are preparing for this difficult and often pricey reality of aging, and found two-thirds say they’ve done little to no planning. In fact, 3 in 10 would rather not think about getting older at all. Only a quarter predict it’s very likely that they’ll need help getting around or caring for themselves during their senior years, according to the poll by the AP-NORC Center for Public Affairs Research. That’s a surprise considering the poll found more than half of the 40-plus crowd already have been caregivers for an impaired relative or friend — seeing from the other side the kind of assistance they, too, may need later on. The poll found most people expect family to step up if they need long-term care — even though 6 in 10 haven’t talked with loved ones about the possibility and how they’d like it to work. Government figures show nearly 7 in 10 Americans will need long-term care at some point after they reach age 65, whether it’s from a relative, a home health aide, assisted living or a nursing home. On average, they’ll need that care for three years.